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OBJECTIVE: To compare the clinical effectiveness of mini-implants (MIs) and conventional anchorage appliances used for orthodontic anchorage reinforcement in patients with class I or II malocclusion with bimaxillary protrusion. MATERIALS AND METHODS: Literature search was conducted through PubMed, Embase, and Cochrane from inception to July 2018. The following Medical Subject Heading terms were used for the search string: "skeletal anchorage", "temporary anchorage devices", "miniscrew implant", "mini-implant", "micro-implant". Standardized mean difference (SMD) and 95% confidence interval (CI) of horizontal and vertical movements of teeth from baseline were used for comparison. RESULTS: A total of 12 studies were included in the final analysis. MI group significantly lowered mesial movement of molars compared to conventional anchorage group (SMD = -1.48, 95% CI = -2.25 to -0.72; P = .0002). There was significantly higher retraction of incisors in the MI group than in the conventional group (SMD = -0.47 mm, 95% CI = -0.87 to -0.07; P = .02). No significant difference was seen in vertical movement of molars (SMD = -0.21 mm, 95% CI = -0.87 to 0.45; P = .52) and incisors (SMD = -0.30, 95% CI = -1.18 to 0.58; P = .5). CONCLUSION: MIs seem to be more effective than the conventional anchorage devices in terms of minimizing unintended mesial movement of molars with maximum retraction of anterior teeth.

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Two-dimensional materials provide extraordinary opportunities for exploring phenomena arising in atomically thin crystals. Beginning with the first isolation of graphene, mechanical exfoliation has been a key to provide high-quality two-dimensional materials, but despite improvements it is still limited in yield, lateral size and contamination. Here we introduce a contamination-free, one-step and universal Au-assisted mechanical exfoliation method and demonstrate its effectiveness by isolating 40 types of single-crystalline monolayers, including elemental two-dimensional crystals, metal-dichalcogenides, magnets and superconductors. Most of them are of millimeter-size and high-quality, as shown by transfer-free measurements of electron microscopy, photo spectroscopies and electrical transport. Large suspended two-dimensional crystals and heterojunctions were also prepared with high-yield. Enhanced adhesion between the crystals and the substrates enables such efficient exfoliation, for which we identify a gold-assisted exfoliation method that underpins a universal route for producing large-area monolayers and thus supports studies of fundamental properties and potential application of two-dimensional materials.

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Two unusual dendrobine-type alkaloids, findlayines E and F (1, 2), along with five known dendrobine-type alkaloids (3-7), were isolated from the stems of Dendrobium findlayanum Par. et Rchb. f. Compound 1 is the first example of dendrobine-type alkaloids with a 2-ethoxy-2-oxoethyl group attaching to the C-2, and compound 2 is a nor-dendrobine-type alkaloid, featuring a 5-decarboxylated structure. The structures of compounds 1 and 2 were elucidated by means of extensive spectroscopic analyses, and their absolute configuration were confirmed by electronic circular dichroism (ECD) calculations. All isolates were evaluated for their cytotoxicity against HL-60, SMMC-7721, A-549 and MCF-7 human cancer cells.

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The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing worldwide. Although gene-environment interactions have been implicated in the etiology of several disorders, the impact of paternal and/or maternal metabolic syndrome on the clinical phenotypes of offspring and the underlying genetic and epigenetic contributors of NAFLD have not been fully explored. To this end, we used the liver-specific insulin receptor knockout (LIRKO) mouse, a unique nondietary model manifesting 3 hallmarks that confer high risk for the development of NAFLD: hyperglycemia, insulin resistance, and dyslipidemia. We report that parental metabolic syndrome epigenetically reprograms members of the TGF-ß family, including neuronal regeneration-related protein (NREP) and growth differentiation factor 15 (GDF15). NREP and GDF15 modulate the expression of several genes involved in the regulation of hepatic lipid metabolism. In particular, NREP downregulation increases the protein abundance of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) and ATP-citrate lyase (ACLY) in a TGF-ß receptor/PI3K/protein kinase B-dependent manner, to regulate hepatic acetyl-CoA and cholesterol synthesis. Reduced hepatic expression of NREP in patients with NAFLD and substantial correlations between low serum NREP levels and the presence of steatosis and nonalcoholic steatohepatitis highlight the clinical translational relevance of our findings in the context of recent preclinical trials implicating ACLY in NAFLD progression.

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Upon assembling the first Gossypium herbaceum (A1) genome and substantially improving the existing Gossypium arboreum (A2) and Gossypium hirsutum ((AD)1) genomes, we showed that all existing A-genomes may have originated from a common ancestor, referred to here as A0, which was more phylogenetically related to A1 than A2. Further, allotetraploid formation was shown to have preceded the speciation of A1 and A2. Both A-genomes evolved independently, with no ancestor-progeny relationship. Gaussian probability density function analysis indicates that several long-terminal-repeat bursts that occurred from 5.7 million years ago to less than 0.61 million years ago contributed compellingly to A-genome size expansion, speciation and evolution. Abundant species-specific structural variations in genic regions changed the expression of many important genes, which may have led to fiber cell improvement in (AD)1. Our findings resolve existing controversial concepts surrounding A-genome origins and provide valuable genomic resources for cotton genetic improvement.

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BACKGROUND AND PURPOSE: Anxiety disorder is a common mental health disorder. However, there are few safe and fast-acting anxiolytic drugs available that can treat anxiety disorder. We previously demonstrated that the interaction of neuronal NOS (nNOS) with its carboxy-terminal PDZ ligand (CAPON) is involved in regulating anxiety-related behaviours. Here, we further investigated the anxiolytic effects of nNOS-CAPON disruptors in chronic stress-induced anxiety in animals. EXPERIMENTAL APPROACH: Mice were intravenously treated with nNOS-CAPON disruptors, ZLc-002 or Tat-CAPON12C, at the last week of chronic mild stress (CMS) exposure. We also infused corticosterone (CORT) into the hippocampus of mice to model anxiety behaviours and also delivered ZLc-002 or Tat-CAPON12C on the last week of chronic CORT treatment via pre-implanted cannula. Anxiety-related behaviours were examined using elevated plus maze, open field, novelty-suppressed feeding and light-dark (LD) tests. The level of nNOS-CAPON interaction was determined by co-immunoprecipitation (CO-IP) and proximity ligation assay (PLA). The neural mechanisms underlying the behavioural effects of nNOS-CAPON uncoupling in anxiety animal models were assessed by western blot, immunofluorescence and Golgi-Cox staining. KEY RESULTS: ZLc-002 and Tat-CAPON12C reversed CMS- or CORT-induced anxiety-related behaviours. ZLc-002 and Tat-CAPON12C increased synaptogenesis along with improved dendritic remodelling in CMS mice or CORT-treated cultured neurons. Meanwhile, blocking nNOS-CAPON interaction significantly activated the cAMP response element-binding protein (CREB)-brain-derived neurotrophic factor (BDNF) pathway, which is associated with synaptic plasticity. CONCLUSION AND IMPLICATIONS: Collectively, these results provide evidence for the anxiolytic effects of nNOS-CAPON uncouplers and their underlying mechanisms in anxiety disorders.

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BACKGROUND: Fracture is a common disease; many factors affect fracture healing. Recent studies have confirmed that hydrogen sulfide (H2S) plays an essential role in bone formation, but most of these studies are drawing conclusions based on animal experiment; whether H2S could promote fracture healing in patients is still unclear. We aim to investigate the change of serum H2S in fracture patients, and analyze its effort on fracture healing. METHODS: This is a single-center, prospective cohort study. Patients with spinal or limb fracture will be recruited. Patient's serum and urine will be collected at baseline for examination (serum H2S, ß-CTX, OC, PINP, 25-OH-VitD3, S-CTX, urinary calcium, and urinary creatinine). All patients will be followed-up for 24 months in outpatients settings, the image of X-ray or CT will be reviewed and fracture healing will be judged by 2 experienced orthopedic physicians. The difference in serum parameters especially H2S will be compared between patients with fracture healed within 9 months and those with fracture unhealed at 9 months. DISCUSSION: Results of the trial could provide insight into influence of H2S on fracture healing. ETHICS AND DISSEMINATION: The study was approved by the ethics committee of School of Medicine UESTC & Sichuan Provincial People's Hospital Ethics Committee. All the participants will be asked to provide written informed consent before data collection. The findings of the study will be published in peer-reviewed journals and will be presented at national or international conferences.

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A cattle-yak, which is a hybrid between a yak (Bos grunniens) and cattle (Bos taurus), is an important livestock animal, but basic questions regarding its physiology and environmental adaptation remain unanswered. To address this issue, the present study examined the species composition and functional characteristics of rumen microorganisms in the cattle-yak of different ages (2 and 3 years old) by metagenomic analysis. We found that rumen microbial community composition was similar at the two ages. Firmicutes, Fibrobacteres, Euryarchaeota, Bacteroidetes, and Proteobacteria were the predominant phyla, with Firmicutes accounting for the highest percentage of bacteria in 2-year-old (48%) and 3-year-old (46%) animals. Bacterial species involved in lignocellulose degradation were detected in the rumen of adult cattle-yaks including Ruminococcus flavefaciens, Ruminococcus albus, Fibrobacter succinogenes, and Prevotella ruminicola, with F. succinogenes being the most abundant. A total of 145,489 genes were annotated according to the Carbohydrate-active Enzyme database, which identified glycoside hydrolases as the most highly represented enzyme family. Further functional annotation revealed specific microflora and genes in the adult rumen that are potentially related to plateau adaptability. These results could explain the heterosis of the cattle-yak and provide insight into mechanisms of physiologic adaptation in plateau animals.

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Understanding the genetic basis of natural variation in grain size among diverse rice varieties can help breeders develop high-yielding rice cultivars. Here, we report the discovery of qTGW2, a new semidominant quantitative trait locus for grain width and weight. The corresponding gene, TGW2, encodes CELL NUMBER REGULATOR 1 (OsCNR1) localized to the plasma membrane. A single nucleotide polymorphism (SNP) variation 1818 bp upstream of TGW2 is responsible for its different expression, leading to alteration in grain width and weight by influencing cell proliferation and expansion in glumes. TGW2 interacts with KRP1, a regulator of cell cycle in plants, to negatively regulate grain width and weight. Genetic diversity analysis of TGW2 in 141 rice accessions revealed it as a breeding target in a selective sweep region. Our findings provide new insights into the genetic mechanism underlying grain morphology and grain weight, and uncover a promising gene for improving rice yield.

RESUMO

Plant architecture is a complex agronomic trait and a major factor of crop yield, which is affected by several important hormones. Strigolactones (SLs) are identified as a new class hormoneinhibiting branching in many plant species and have been shown to be involved in various developmental processes. Genetical and chemical modulation of the SL pathway is recognized as a promising approach to modify plant architecture. However, whether and how the genes involved in the SL pathway could be utilized in breeding still remain elusive. Here, we demonstrate that a partial loss-of-function allele of the SL biosynthesis gene, HIGH TILLERING AND DWARF 1/DWARF17 (HTD1/D17), which encodes CAROTENOID CLEAVAGE DIOXYGENASE 7 (CCD7), increases tiller number and improves grain yield in rice. We found that the HTD1 gene had been widely utilized and co-selected with Semidwarf 1 (SD1), both contributing to the improvement of plant architecture in modern rice varieties since the Green Revolution in the 1960s. Understanding how phytohormone pathway genes regulate plant architecture and how they have been utilized and selected in breeding will lay the foundation for developing the rational approaches toward improving crop yield.

RESUMO

The chloroplast RNA splicing and ribosome maturation (CRM) domain-containing proteins regulate the expression of chloroplast or mitochondrial genes that influence plant growth and development. Although 14 CRM domain proteins have previously been identified in rice, there are few studies of these gene expression patterns in various tissues and under abiotic stress. In our study, we found that 14 CRM domain-containing proteins have a conservative motif1. Under salt stress, the expression levels of 14 CRM genes were downregulated. However, under drought and cold stress, the expression level of some CRM genes was increased. The analysis of gene expression patterns showed that 14 CRM genes were expressed in all tissues but especially highly expressed in leaves. In addition, we analyzed the functions of OsCFM2 and found that this protein influences chloroplast development by regulating the splicing of a group I and five group II introns. Our study provides information for the function analysis of CRM domain-containing proteins in rice.

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Nowadays, antibiotic resistance genes (ARGs) have been characterized as an emerging environmental contaminant, as the spread of ARGs may increase the difficulty of bacterial infection treatments. This study evaluates the combination of ultraviolet (UV) irradiation and chlorination, the two most commonly applied disinfection methods, on the degradation of sulphonamide resistance sul1 genes. The results revealed that although both of individual UV and chlorination processes were relatively less effective, two of the four combined processes, namely UV followed by chlorination (UV-Cl2) and simultaneous combination of UV and chlorination (UV/Cl2), delivered a better removal rate (up to 1.5 logs) with an observation of synergetic effects up to 0.609 log. The mechanisms analysis found that the difference of DNA size affected sul1 genes degradation by UV and chlorination; targeted genes on larger DNA fragments could be more effectively degraded by UV (1.09 logs for large fragments and 0.12 log for small fragments when UV dose reached 432 mJ/cm2), while to degrade ARGs on smaller DNA fragments required less free chlorine dosage (10 mg/L for small fragments and 40 mg/L for large fragments). The sequential combination of UV and chlorination (UV-Cl2) used the corresponding reactivity of both processes, which could be the reason for the synergetic effect. For UV/Cl2 process, the formation of reactive oxygen species (ROS) contributed to the synergetic effect. Scavenger analysis showed that the contribution of ROS to the sul1 gene reduction was 0.004 to 0.273 log (up to 45.5 % of the total synergy values), and among the two major reactive species in UV/Cl2 system, HO was the more important radical, while the contribution of Cl was negligible. Besides, UV/Cl2 process also used the corresponding reactivity of both processes to generate the remaining synergy values when excluding the contribution by reactive radicals. These findings provide a thorough understanding of the effects of UV and free chlorine on the degradation of ARGs and indicate the potential to utilize the combined processes of UV and free chlorine in water or wastewater treatment practice to control the dissemination of antibiotic resistance.

RESUMO

Wool and hair fibres consist of a variety of proteins, including the keratin-associated proteins (KAPs). In this study, a putative ovine homologue of the human KAP21-2 gene (KRTAP21-2) was identified. It was located on chromosome 1 as a 201-bp open reading frame (ORF) in the ovine genome assembly from a Texel sheep (v.4 NC_019458.2: nt122932727 to 122932927). A polymerase chain reaction- single strand conformation polymorphism (PCR-SSCP) analysis of this ORF, and subsequent DNA sequencing, identified five sequences (named A-E). The putative amino acid sequences that would be produced, shared some identity with each other and with other KAPs, but they were most similar to ovine KAP21-1, and phylogenetically related to human KAP21-2. The location of the ovine KRTAP21-2 sequence was consistent with the location of human KRTAP21-2, and this suggests they represent different variant forms of ovine KRTAP21-2. Variation in this gene was investigated in 389 Merino (sire) × Southdown-cross (ewe) lambs. These were derived from four independent sire-lines. The sequence variation was found to be associated with variation in five wool traits: including mean staple length (MSL), mean fibre diameter (MFD), fibre diameter standard deviation (FDSD), prickle factor (PF), and greasy fleece weight (GFW). The most persistent effect of KRTAP21-2 variation was with variation in MSL; with the MSL of sheep of genotype AC being 12.5% greater than those of genotype CE. A similar effect was observed from individual variant absence/presence models. This suggests that KRTAP21-2 should be further investigated as a possible gene-marker for improving MSL.

RESUMO

The aim of this research was to identify variation in the yak lipin-1 gene (LPIN1) and determine whether this variation affects milk traits. PCR-single stranded conformational polymorphism (PCR-SSCP) analysis was used to detect variation in the 5' untranslated region of LPIN1 in 500 yaks from four populations: Tianzhu white yaks, Qinghai yaks, wild × domestic-cross yaks and Gannan yaks. Four unique PCR-SSCP patterns, representing four different DNA sequence variants (named A, B, C and D), were observed. These contained six single nucleotide polymorphisms. Female Gannan yaks with BC genotype produced milk with a higher fat content (P < 0.001) and total milk solids (P < 0.001), than those with the AA, AB and BB genotypes. These results would suggest that LPIN1 is having an effect on yak milk fat synthesis.

RESUMO

A chemical investigation on the 95% ethanol extract of the aerial part of Gelsemium elegans resulted in the isolation of three new gelsedine-type indole alkaloids, 14ß-hydroxygelselenidine (1), 11-methoxygelseziridine (2), and 14ß-hydroxygelsedethenine (3). Structural elucidation of all the compounds was accomplished by spectral methods such as 1 D and 2 D NMR, IR, UV, and HRESIMS. The isolated compounds were tested in vitro for cytotoxic activities against five human non-small-cell lung cancer cell lines. Consequently, alkaloid 3 exhibited cytotoxic activities for all tested tumor cell lines with IC50 values from 8.3 to 9.8 µM.[Formula: see text].

RESUMO

The palea and lemma are floral organ structures unique to grasses; these structures form the hull and directly affect grain size and quality. However, the molecular mechanisms controlling the development of the hull are not well understood. In this study, we characterized the rice (Oryza sativa) abnormal flower and grain1 (afg1) mutant, a new allele of OsMADS6. Similar to previously characterized osmads6 alleles, in the afg1 floret, the palea lost its marginal region and acquired the lemma identity. However, in contrast to other osmads6 alleles, the afg1 mutant showed altered grain size and grain quality, with decreased total starch and amylose contents, and increased protein and soluble sugar contents. The analysis of transcriptional activity suggested that AFG1 is a transcriptional activator and may affect grain size by regulating the expression levels of several genes related to cell expansion and proliferation in the afg1 mutant. These results revealed that AFG1 plays an important role in determining palea identity and affecting grain yield and quality in rice.

RESUMO

Objective: To compare short-term effectiveness between robot-guided percutaneous minimally invasive pedicle screw internal fixation and traditional open internal fixation in the treatment of thoracolumbar fractures. Methods: The clinical data of 52 cases of thoracolumbar fracture without neurological injury symptoms admitted between January 2018 and May 2018 were retrospectively analyzed. According to the different surgical methods, they were divided into minimally invasive group (24 cases, treated with robot-assisted percutaneous minimally invasive pedicle screw internal fixation) and open group (28 cases, treated with traditional open internal fixation). There was no significant difference between the two groups in the general data such as gender, age, cause of injury, fracture segment, thoracolumbar injury classification and severity score (TLICS), preoperative back pain visual analogue scale (VAS) score, Oswestry disability index (ODI) score, fixed segment height, and fixed segment kyphosis Cobb angle ( P>0.05). The operation time, intraoperative blood loss, and hospitalization time of the two groups were recorded and compared; as well as the VAS score, ODI score, fixed segment height, and fixed segment kyphosis Cobb angle of the two groups before operation and at 3 days, 1 month, 6 months, and 10 months after operation. CT scan was reexamined at 1-3 days after operation, and the pedicle screw insertion accuracy rate was determined and calculated according to Gertzbein-Robbins classification standard. Results: The operation time of the minimally invasive group was significantly longer than that of the open group, but the intraoperative blood loss and hospitalization time were significantly shorter than those of the open group ( P<0.05). There were 132 pedicle screws and 158 pedicle screws implanted in the minimally invasive group and the open group respectively. According to the Gertzbein-Robbins classification standard, the accuracy of pedicle screws was 97.7% (129/132) and 96.8% (153/158), respectively, showing no significant difference between the two groups ( χ 2=0.505, P=0.777). The patients in both groups were followed up 10 months, and there was no rejection or internal fixation fracture. In the minimally invasive group, the internal fixator was removed at 10 months after operation, but not in the open group. The VAS score, ODI score, fixed segment heigh, and fixed segment kyphotic Cobb angle of the two groups were improved in different degrees when compared with preoperative ones ( P<0.05). Except that the VAS score and ODI score of the minimally invasive group were significantly better than those of the open group at 3 days after operation ( P<0.05), there was no significant difference between the two groups at other time points ( P>0.05). Conclusion: Robot-assisted percutaneous minimally invasive pedicle screw internal fixation for thoracolumbar fractures has significant advantages in intraoperative blood loss, hospitalization time, and early postoperative effectiveness and other aspects, and the effect of fracture reduction is good.

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New structured lipids with 1,3-oleic-2-medium chain (OMO) triacylglycerols were synthesized by promoting acyl migration in Lipozyme RM IM catalyzed interesterification between coconut oil (CO) and high oleic rapeseed oil (HORO). Results from an orthogonal design L25(55) showed that the maximal yield of OMO-structured triacylglycerols was 45.65% under the following conditions: the molar ratio of CO to HORO, 50:50; enzyme dosage, 12 wt%; reaction temperature, 60 °C; reaction time, 2 h; water activity, 0.07. Low water activity showed a high rate of acyl migration (10.86% vs 5.07% no water system), which promoted OMO synthesis due to medium-chain fatty acid migration to the sn-2 position. In a low water content (5%) system of the molecular dynamics simulation, water molecules stabilized the whole structure of RM IM through hydrogen bonding, which helped fix lipase-catalyzed active sites, making substrates more easily inserted into active sites, resulting in increased enzyme activity.

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The keratin-associated proteins (KAPs) are constituents of cashmere fibers and variation in many KAP genes (KRTAPs) has been found to be associated with fiber traits. The gene encoding the high-sulphur KAP28-1 has been described in sheep, but it has not been identified in the goat genome. In this study, a 255-bp open reading frame on goat chromosome 1 was identified using a search of similar sequence to ovine KRTAP28-1, and that would if transcribed and translated encode a high sulphur KAP. Based on the analysis of polymerase chain reaction (PCR) amplicons for the goat nucleotide sequences in 385 Longdong cashmere goats in China, five unique banding patterns were detected using single-stranded conformational polymorphism (SSCP). These represented five DNA sequences (named variants A to E) and they had the highest resemblance to KRTAP28-1 sequences from sheep, suggesting A-E are variants of caprine KRTAP28-1. DNA sequencing revealed a 2 or 4-bp deletion and eleven nucleotide sequence differences, including four non-synonymous substitutions. Of the four common variants (A, B, C and D) found in these goats, the presence of variant A was associated with decreased mean fiber diameter and this effect appeared to be additive. These results indicate that caprine KRTAP28-1 variation might have value as a molecular marker for reducing cashmere mean fiber diameter.

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